Growing from seed

Growing your own plants from seed is very satisfying

by Michael Smith (Veshengro)

Growing your own plants from seed is easy and very satisfying even on the smallest scale. The sight of green shoots poking through dark compost arouses a feeling of parental pride in almost everybody. And growing from seed is the only way possible for some vegetables anyway. Don't get fooled into buying carrot or parsnip plugs; they don't work well.

Sowing seeds

There are three ways to start seeds off:

Directly outside – this is best for root vegetables, and is possible for most other vegetables, and should be done when the soil is warm.

Inside in pots – this gives a higher success rate, as you can take better care of your seedlings, and the likes of slugs and snails, etc. don't have a change of destroying them before they have even “hatched”. Plants like tomatoes and courgettes which are all too easily damaged by frost can get off to an earlier start if sown inside first.

Inside in modules – these only have to be transplanted once when they are transferred outside. This can be very handy if you have a distant allotment when you can get your plants established in the safety of your own back garden.

'Inside' can mean a light place in the house or shed, a conservatory or a greenhouse.

What you will need

Seed modules or paper pots. In the case of the latter you can also use anything else you would want for pots, such as proper flower pots (the plastic kind or the terracotta kind), or, yoghurt pots or make your own paper pots using the paper potter. Alternatively, if you have trays you can use you can make grow tubes by using toilet roll inners.

In addition a light place, not too hot, such as a North facing windowsill where your seeds can grow undisturbed.

As said earlier well washed yoghurt pots are fine in lieu of flowerpots, but make sure you make a nice hole in the bottom (of the container) for drainage. You do not want your seedlings to drown. More plants are killed by over watering then buy not giving them enough.

When it comes to the potting compost you could buy a specially formulated seed compost from the garden centre. This has been sterilised so what comes up is what you put in, theoretically. It does not always work that way either. On the other hand you can use your homemade compost, just get some sand to mix with it for better drainage.

What to grow and how?

Onions cabbages and fennel are really easy to sow in modules but tomatoes and marrows do better in pots. Lettuce and other salad greens can be sown outside or in modules. I would suggest to sow them into large shallow containers or such outside as soon as the soil warms up a little.

Peas and beans can be sown outside or in modules and I always start mine off in pots early for an early start and put more in later straight into the containers in which they will grow.

Don't bother trying to sow parsnips or carrots in small containers or modules because they hate being disturbed for transplanting. You will see from what I have just said that it makes no sense at all to buy some plants as plugs, such as carrots, parsnips and one or two others.

When to sow?

The time as to then when very much depends on your area of operation and region.

A good time to start growing lettuce seeds on a windowsill inside, in the British Midlands, for instance, would be early March. If in doubt, look out of the window first and think if you would be happy left outside there! Remember that your little vegetable plants will move to the outside quite soon and you don't want them to get too big before you plant. Though with some that can be an advantage, such as for cabbages, as I have been told.

Some of the seed companies have a sowing and planting calculator on their websites nowadays or other information. In the United States you can check with your extension offices as to when the ideal time is. The growing zones there vary much more than they do in, say, Britain or Germany or Holland.

How to sow?

Seeds vary in size and shape a lot. Some are huge, like avocado seeds, while others are like fine dust such as rhododendrons, but you are not going to sow rhododendrons because you can't eat them and avocados may not ripen in our climate. Fortunately vegetable seeds fall between these extremes.

If the seeds are large enough to handle individually, like the little bullets of the brassica family, try to space them out evenly around the container. Big seeds like beans can go two or three into a yoghurt pot. Some recommend that you pull out the weakest seedling to let just one live and grow up healthily, but with beans I suggest, as with peas, to let them all live together as one.

The general rule is to cover the smaller seeds with as much soil as they are tall. Bigger seeds like peas can be pushed into the soil as far as the first joint of a middle finger.

What to do

It is always suggested to make sure that, first of all, your pots are clean, and come with a drain hole in the bottom if they didn't start life as a flowerpot.

Check your compost is fine and friable, not too wet or too dry. Some say that you should not, for instance, use last year's compost and that has "best before" dates and loses nutrients over time. I have, however, successfully used almost any type of compost bar that kind that is way too sterilized or peaty that it is dead.

Don not, against the recommendation of many, fill your container all the way up to the top. Instead just fill to the flowerpot rim. That rim is there so that water does not overflow when you water the plants. Buy or make yourself a tamper to press down the soil and give it a tap to settle any air spaces.

Put a little water in the sink and place your container(s) in it. You want them to stand there and not float. The compost will slowly soak up the water and when the top starts to look wet, take them out and stand them somewhere they can drain without getting in the way. Plant your seeds in a way appropriate to their size - check the seed packet for details.

You could now carefully stretch cling film over the top, or cover with a polythene bag secured with an elastic band. If you have some correctly sized pieces of glass, use these to cover the containers, or you could use some polycarbonate sheets. This means the moisture in the compost won't be lost from evaporation and you don't need to water again until the seeds are through. Place the container on a windowsill where it will not have the sun shining directly on it or be right on top of a radiator.

In ten days or so, the soil will start to heave upwards and soon you will see the first little green tips of your seedlings forcing their way up to the light. Take off the cling film, polythene bag or “glass” and cautiously feel the compost with a finger. If the top is dry, stick your finger in a bit deeper and see if it feels damp further down. Do not overwater to avoid “dampening off”, a fungal disease that will make your seedlings keel over and die.

Some “experts” claim that you should only use fresh tap water on your seedlings as rain water can contain microorganisms that cause “damping-off” but tap water will do the very same if the conditions are there. It has little to do with what kind of water but everything to do with too much watering.

Alan Titchmarsh has said many a times on his shows, and it is a proven fact, that more seedings and plants are killed by overwatering than by underwatering.

As soon as the seedlings are big enough to handle, if there are a lot in your container, prick them out, using a dibblet (basically a small thin dibber), and move them on into individual pots or trays.

Plants hate being overcrowded.

If you only want a few plants pull up the weakest seedlings to give the rest some space. Push an old seed label or dibblet carefully into the soil to loosen it and separate each seedling by holding it with one leaf, not by the stem. If you have only one seedling in a pot, leave it in there until it has grown about four true leaves. When transplanting seedlings try to plant them down as far as you can, so the lowest leaves are just resting on the soil.

Plants grown on a windowsill often get leggy when they are looking for light. Try to remember to turn the container regularly. Seedlings need lots of light so you may need to change windowsills if they get too leggy.

As the plants grow, stand them outside on sunny mild days to get the full benefit of light and air. If a mild night is forecast and they seem to be growing well, leave them outside overnight. Gradually harden them off over about a week to ten days, before planting them outside. If a frost seems likely just after your plants have gone into the ground, don't panic! Covering them with a few sheets of newspaper or a piece of horticultural fleece overnight will be sufficient protection against most spring frosts.

A good investment, if you have the space, is to make or buy a small coldframe. You can move your plants into there from you windowsill already earlier and let them carry on growing there until they are big enough to go in.

My favorite way of sewing in “pots” is using “growtubes” and “paper pots”, both homemade and upcycled. No cleaning needed and you just plant the pots with the plants into the ground. Only, do not soak them in the sink or otherwise as described for general pots.

Sowing in modules

Sowing in modules has become very popular commercially in the last few years. New module trays in various sizes are available from most garden centres but quite often secondhand module trays, which look like little plastic honeycombs, are available from nurseries at very low cost. If you use these make sure they are thoroughly washed and dried in the sun before filling them. The original recyclable module tray is the cardboard eggbox. Tap the seedlings out at planting time and put the soggy cardboard remnants on the compost heap, or, alternatively, don't even disturb the little plants and simply separate the carton sections and plant in the cardboard pots.

You can, as I have said already, also use old toilet roll inners. Plants can be transplanted directly without removing them from the tubes, as these will rot down naturally in the soil.

Sowing outside

Sowing outside is probably the easiest way but also the one with the more hazards attached.

Choose a day when you feel happy outside without a coat as this will usually be a fair indication that the soil is warm enough.

Ensure the place you want to sow is free of weeds and rake the soil gently free of stones and lumpy mud in order to create what is called a fine tilth.

As some plants need more room than others I suggest you look at the instructions on the packet as to how far the plants and the rows should be apart. However, depending on what kind of vegetable garden you create you may want to put stuff closer together to use maximum space and, to some extent, ignore the instructions. If you are working the square-foot method you want to have maximum possible density per inch and it may be a case of “trial and error” to get it right. In fact, a lot of gardening, vegetables and flowers, is a trial and error thing more often than not.

In order to sow draw a shallow line in the earth with a stick or the edge of a hoe for larger seeds like peas and beans. Beans and peas are often set in a double row so they can support each other as they grow. Mark the top and bottom of your line with a stick so you can find it again, and, ideally, maybe also put a tag on the stick that tells you what you have sown in that row.

Sowing the seed is the same as in a pot, but sprinkle them lightly and rake over just enough to cover them. If the soil is very dry, water where you are sowing really well, then cover the seeds with dry soil. Peas are usually spaced about a thumb joint apart, broad beans about 8cm/3" apart. French beans go a little wider apart. Runner beans can be more than one seed per hole and remember you will need support for beans other than broad beans, and that is also true for French Beans, Dwarf beans and Peas.

Look for your seedlings - some will come up fast, like cabbages, and others are very slow, especially parsnips. It is a good idea to sow radish and parsnip seed in the same spot because not only will it remind you where the parsnips are but the radishes will be ready to eat by the time the parsnips are starting to emerge.

In very hot weather lettuce seed goes to sleep, so if it hasn't come up, don't worry because it probably will germinate as soon as the weather changes. Your seedlings may need thinning out if they are growing very close together.

So, good luck and enjoy your produce.

© 2011